Oil burner



July l, 1941 L. o. sELBY 2.247.858

l on. BURNER i Fi1`ed March 4. 1939 l I I 3l.

Fmg Power 0|( Valve Patented July-1 11941 OIL BURNER Lynn Otis Selby, Cromwell, Conn., assignor to The Sparmal Engineering Corporation, a corporation of Connecticut Applicatie Maren 4, 1939, serial No. 259,881

My invention relates to oil burners. n

It has among its objects to provide an improved control mechanism for combined burners of the type including a preheating and maintaining burner, herein called the distillate burner, and

a main burner, herein called the power burner,

preheated and maintained hot by the distillateburner ready for starting and operation at any time whereby an entirely automaticv control of both ofthese burners is made possible. Further in, however, an electric spark plug 'l is provided to ignitev the outer wick. Further, the fuel supply from a constant level float chamber 8 has its objects of my invention are to provide such control mechanism including an improvedautomatic starting mechanism for the distillate burner, and improved automatic controlling mechanism for the power burner including improved controlling mechanism for the fan motor thereof when the power burner is shut down, these mechanisms being so connected and cooperating e as to be under the control of a single control member. Still further objects of my invention are to provide such improved controlling mechanism including improved time control mechanism operating in such manner as to insure successful automatic-starting and automatic operation, while insuring satisfactory control of both burners and enabling the power burner to be shut down without smoking. Theseand other objects and advantages of my improvements will, however, hereinafter more fully appear.

In the accompanying drawing, I have shown for purposes of illustration two embodiments which my invention may assume in practice.

Inthe drawingy l Figure 1 isa. side elevation, partiallyin section, of a combined distillate and power burner adapted for use with my improvements;

Fig. 2 is a wiring diagram of one form of controlling mechanism therefor; 1

Fig. 3 is a detail of the ignition controlling time switch;

Fig.'4 is a like detail view of the power burner fan and valve controlling time switch, and

Fig. 5 is a wiring diagram of a modified forml of controlling mechanism,

In the illustrative construction shown in Fig-` 11 claims. (c1. 15s-2s) same is of the general construction disclosed in my application mentioned, including a; burner base I having a vaporizing chamber 2 connected l in a usual manner to oil grooves 3 and 4 equipped with usual wicks 6, while the vaporizing charnber Ais provided with a usual carbon leg 5. Heremaximum flow controlled by a metering valve t Aandis connected by a pipe III to a normally closed solenoid valve II which controls the flow through a pipe I2 connected to the carbon leg 5. Also, improved controlling mechanism, hereinafter described, controls both the operation of the spark plug l and the solenoid valve II.

Referring tothe power burner. the same also, as heretofore, includes a vaporizing chamber I3 disposed coaxially within the vaporizlng chamber 2 of the distillate b'urner, and an air supply pipe I4 delivering axially through the-vaporizing chamber. The oil supply I5 to the vaporizing chamber I3 also is controlled by a solenoid valve I6 which, in turn, controls the flow through a pipe I1 from the constant level float valve chamber 8; the maximum flow being controlled by a` solenoid valve I6 and this fan motor, as hereinafter brought out.l

Referring to the controlling 'mechanism shown in Figure 2, attention is rst directed to the automatic controlling mechanism for the spark plugl 1. Herein a. manual switch 24 vis provided in one side of the line and asuitable time switch 25 is provided controlled by this'switch 24. This time switch may be of any suitable type, but I have shown the same, for simplicity, of the thermostatic type including a heating coil 25a and a normally closed thermostatic switch element 25b carrying'a contact `2lic and adapted, after a predetermined heating period, as, for example, three to ve minutes, to move said contact to disengage a contactA 25d controlling current flow through'a primary coil 25 of a transformer T having a secondary coil 21 connected to the spark plug 1. Thus, when the switch 24 is closed, current will fiow from the line through the switch 24 and the transformer T to energize. the spark plug 1, and a spark will thus continue to be transmitted to theouter wick 6 until after the expiration of the desired time limit, when the thermostatic element 2517 is opened, thereby interrupting operation of the spark plug circuit.

At the same time that the time switch 25 is started by throwingthe switch 24, it will also be observed that an actuating coil 28 for the lsolenoid valveA I I of the distillate burner isenergized in such manner as to open this-valve and thereby establish normal operating oil flow to the distillate burner.

Referring to the control mechanism for thepower burner, the closing of theswitch 24 also `sets a suitable time switch 29 in operation which controls the operation of the solenoid valve I6 of the power burner and of the fan motor 2| for the latter. The time switch 29 illustrated herein (Fig. 4) is of the same general construction kas time switch'25 save that it is of the type having its contacts normally open, and that it is adapted to provide a longer time interval. Herein, a movable contact 29a is carried by a bimetallic element 29h which is heated by a heating element 29e .of high resistance or suitably heat insulated, and this contact 29a is adapted to engage a stationary contact 29d, after a predetermined heating interval, hereinV 15 or 2O minutes, the time necessary for the distillate Iburner to bring the oil in the vaporizing chamber I3 of the power burner -up to such a temperature as to vaporize the same and maintain combustion when this vapor is mixed with the air passing through the tube I4. Herein, the fan motor 2| and actuating coil 30 for-the soienoid valve I6 of the power burner are connected in parallel, a. suitable pressurestat switch 31| re-v sponsive to the pressure in the boiler 32-l also controlling the circuit to the actuating coil A3|). Herein,.it will also bev-noted that a'thermostatic switch generally indicated at 23, is also mounted on the lburner base I, herein inside of a suitable burner enclosing casing 32a, and adapted to control the circuitfof4 the fan motor 2| #As shown, (Fig. 2) this switch includes a bimetallic'strip 33 responsive to changes in temperature'of --the burner base I and carrying a contacty 34 conl ductor 35a in a`v secondaryv fan motor circuit-for' energizing the fan motor from the line after its circuit throughA time switch 29 has been interrupted by openingv of Aswitch 24.` Herein, this bimetallic element 33 is adapted Vto-be main'`L tained in circuit -closing position`- while both vthe distillate and power burners arein operation, but is adapted to break Vthe circuit through the contacts 34, -35, a-suitable time after the-power burner-has been shut down,-here,- for'exampla ten to'flfteen minutes. 1 j

--In the operation of thel burners equipped with myimproved control mechanism, it will be evident that it is only necessary for the operator to close the switch 24 to start both burners in operation. When this switch vis closed, thepri mary 26 of the transformer is energized in such manner as to cause operation of the sparkplug 1. At the same time,` the actuating coil 284of the solenoid valve II of the distillate burner is openedto supply oil from the constant level float chamber 3 to 4that burner. uThe spark plug 1 will continue to operate and ignite the outer wick i', the ilow of current to the spark plug being interrupted after the predetermined time interval by the opening of the contact 25c of the time switch 25. In the meantime, the current supplied to the time switch 23 will set the time switch 29 in operation in such manner that this time switch, after a predetermined time, herein 15 to 20 minutes, will close the circuits to the fan motor 2|, pressurestat switch 3|, and actuating coil 3II of the solenoid valve I6 oi' the power burner. These circuits are only energized when the distillate burner has brought the vaporizing parts of the power .burner to such temperature as to generate sumcient vapor to maintain combustion when the vapor is mixed with the air supplied through the tube I4. The thermostatic switch 23 also remains open during the operation of the distillate burner and until the power burner has suiiiciently heated the bimetallic element of this switch to cause it to close. At any time during the operation of the burners, should the pressure generated in the boiler 32 be excessive, the pressurestat switch 3l will'operate to interrupt the flow through 'the actuating coil 30 of the solenoid valve I6 of the power burner, and thereby permit this valve to close and stop the power burner. Further, this switch 3| will also automatically reestablish this circuit and thereby start the power burner when the pressure in the yboiler 32returns to normal, both this starting and stopping of the power burner being independent of the delay imposed by the time switch 23, since this switch 23 continues to hold its contacts 29a, 23d closed. Whenever the power burner is shut down :by the switch 3|, however, it will be observed that the fan motor 2|` remains in operation so thatno smoking occurs, the circuit of-this Ian motor being maintained through the time switch 23 irrespective oi whether or vnot the power burner is shut down by switch 3| suiliciently longto cause the burner base thermostatic time switch 23 to open.` Here itv will .beunderstood that the heat of thelldistillate burneralone is not sulcint to'kepth switch 23,closed, this switch thus .being responsive to. starting and stopping of the power burner and by the'time switch 23, the latter switch remainingA closed until theburner base is cooled sum ciently to cause this switch to open. I

l11i-Figure 5-I have4 illustrated a modified form of controlling mechanism. In this control mechanism, whereinI the corresponding operating parts of the burner mechanisms areiindicated bythe same numbers as used in Figui-e2, it 'will be observed that, after coil 3i has timed the spark andthe other31 has timed the power burner o il valve and fan motor for the desired long heating period, instead of two time switches having their heating coils constantly in circuit, as herefore, heating coil 36 is cut out, while heating coil 31 is switched into a circuit including in series therewith the winding of relay. 40 and a variable resistance 33, thus greatly reducing the current passing .through heating-coil 31. Further, it will be observedthat in this construction magnetic relays 39 and 4l are used, of which the relay-33 controls the circuit through the coil 36, while the relay 4II-y controls the circuit of the heating coil 31. Further, an additional magnetic relay 4| is provided to control the interruption of the fan motorV circuit. Of these magnetic relays, the relayv 39, through contacts 38a and 39h, also controls the spark and heater coll 35, and through contacts 33o, the time delayed picking up of relays 40 and 4|, while contacts 39d control the holding coil circuit for relay 33. Contacts 40a control the circuit to resistance 33 and heating coil 31 with a twenty minute delay for the operation of relays 40, 4I, while contacts 4Gb control the normal circuit of the fan motor 2| and the energization of the coil of relay 4| from a supplementary line connection 40e, and contacts 40d control the circuit to the pressurestat switch 3| 'and the actuating coil 30 of oil valve I6. Further, contacts lla of relay 4| control the vheating circuitfor heating coil 36 of relay 39while contacts Mb control a fan motor circuit which remains closed after the relay 40 has dropped upon opening of the switch 24. Here, however, it will be noted that a bimetallic stack switch 23a, responsive to the stack heat of the power-burner to close its contacts 23h, is so connected in the circuit of the holding coil 'of relay ll as to cause this relay to drop when, a predetermined time after the power burner is shut down, the switch 23a opens its circuit, as heretofore described; the auxiliary circuit of the fan motor being broken at contacts Hb as this relay 4| drops. A manual switch Blais also provided inthe circuit for coil 30 of solenoid valve I6 for the power burner, permitting the power burner to be shut down without maintaining steam pressure in the boiler. It will be understood, moreover, that when this switch 3|a is open, the power burner is ready for instant resumption oi operation upon closing thel switch, just as ,in the-case when this circuit is opened by pressurestat switch 3|, as above described. y v

Here it will be understood. thatHI also, con

template the location of the switch -23, slliownin Figures 1 and 2, in the stack or elsewhere, rather than adjacent the burner base, so long as the same is responsive to the temperature of the power burner. Also, it will be understood that with the control mechanism shown in Iliig- 3 `What I claim as new and desire to secure by Letters Patent is:

1. In combination, a pair of oil burners hav--` ing oil supplies and one burner preheating the other, valves controlling said oil supplies, a manually operable control member. ignition mechanlsm for said preheating burnercontrolled by operation of said member, and mechanism likewise controlled by said member for automatically opening the valve of said preheating burner and subsequently disabling said ignition mechanism and opening the valve of the preheated burner after a preheating operation while maintaining the valve of said preheating burner open to maintain4 said preheated burner constantly preheated ready for immediate starting.

2. In combination, a pair of oil burners having oil supplies and one burner preheating the other, valves controlling said oil supplies, a manually operable -control member, ignition mechanism for said preheating burner including time control means controlled by operation of said member, starting mechanism for said burners likewise controlled by operation of said member including means for opening the preheating burner valve upon operation lof said ignition mechanism and having time control means for opening said preheated burner valve following a' predetermined preheating operation while maintaining the valve of said preheating burner open to maintain said preheated burner constantly preheated ready for immediate starting, and mechanism for starting and stopping said preheated burner in accordance with demands for heat while continuing tornaintain the valve of said preheating burner open to maintain said preheated burner constantly preheatedready for starting. Y

- 3. In combination, a pair of oil burners, one preheating the other, and the latter having an vair supply including a fan motor, means for starting and shutting down said burners, and

' means effective only upon the -shutting down ure 5, a switch 23 may be used on'the burnerba'se if desired, in lieu of a stack switch. l

As a result of my improved construction, it is made possible to con'ne the necessary action of the operator-to opening and closing the main closed only for a suiiicient time to insure light-- ing of the wick. Further, the valves for the two burners are successively f opened inA the desired sequence, while both thevalve `for the power burner and the fan' for the latter are so controlled by the time switch, pressurestat switch, and the switch on the burner. base, as satisfactorily to meet the varyingrequirementsof the.

device in operation. l

While I have in this application specifically described two embodiments which my invention may assume in practice, it. wi1l be understood that these forms ofthe same are chosen for purposes of illustration, and that the invention may be modied and embodied in various other forms without departing from its spirit or the scope of the appended claims.

of'jsaid preheated burner and operating only whenA lthe preheating burner is also shut down for maintaining said fan motor in operation for atime interval after said starting and shutting down means has been moved to shutting ldown position. v v

4. In combination, a pair of oil burners, one preheating the other, and the latter having an air supply :including a fan motor, mechanism for starting and stopping said burners including means for starting and stopping said preheated b urner while maintaining said preheating burner in operation, and burner temperature responsive means inoperative test-op the fan whilev said mechanism is in starting position and operative .tolbreak the circuit of said fan motor after a time interval following the movement;r of said mechanism to stopping position.

5. In combination, a pair of oil burners, one preheating the other, and the latter having an air supply including a fan motor, mechanism for starting and stopping said' burners including means for starting and stopping said preheated burner while maintaining the preheating burner and fan motor in operation, and burner temperature responsive means controlling the circuit of said .fan motor and open during opera tion of said preheating burner only and closed during operation of said preheated burner and opening said fan motor circuit after a ftime inrterval following the movement of saidmechanism to stopping position.

6. In combination, a pair of oil burners, one preheating .the other, and the latter having an air supply including a fan motor, means for starting and stopping sai-d burners, a time delay switch controlled thereby and controlling the starting of said fan motor, and burner temperature responsive means for effecting stopping of `said fan motor af-ter a time interval followy ing the movement of said starting and stopping means to stopping position.

7. In combination, a pair of oil burners, one preheating the other, and the latter having an air supply including a fanl motor, separate oil supplies for said burners, electromagnetically operated valves controlling said oil supplies, means for starting and stopping said burners, a time delay 'switch controlled thereby and controlling the 'starting of said motor and ythe opening of the valve for said preheated burner, means for stopping said preheated burner while maintaining said preheating burner and fan motor in operation, and means responsive to heat generatedby said preheated burner for stopping said fan motor after a time `interval following the movement of said first mentioned means to stopping position.

8. In combination, a pair of oil burners, one preheating the' other, and the latter having an air supply lincluding a fan motor, means for starting and stcppingsaid burners, a time delay switch controlled thereby and controlling said motor, and means not responsive to the operating temperature of said preheating burner alone and responsive to heat generated by said preheated burner for stopping said fan motor after a time interval following movement of said first mentioned means to stopping position.

9. In combination, a pair of oil burners, one preheating the other, an'd the latter having an air supply .including a fan motor, means for stopping and starting said preheated burner While maintaining said preheating burner in operation including a time delay switch controlling said motor, means for starting and stopping the preheating burner, a switch con-trolling the operation of said time delay switch, and temperature responsive means controlled by the heat generated by said preheated burner for stopping said fan motor a time interval after said preheating burner is stopped and said switch is opened.

l0. In combination, a pair of oil burners, one preheating the other, and the latter having an air supply in-cluding a fan motor, means responsive to the heat generated by both of s aid burners for shutting down said preheated burner while maintaining said preheating burner and fan motor in operation, means for shutting down both,

of said burners, and means responsive to the heat generated by said preheated burner for maintaining said fan motor in operation for a time interval after said second mentioned means has been operated to shut down said burners.

1-1. In combination, a pair of oil burners having oil supplies and one burner preheating the other, air supply means for the preheated burner including a fan motor, mechanism for starting and stopping said preheated burner while maintaining said preheating bumerpand fan motor in operation, mechanism for starting and shutting down both burners, and thermostatic means adjacent said burners land heated by both burners for maintaining said fan motor in operation ollowing movement of said mechanism into position for shutting down both burners.

12. In combination, a. pair of oil burners, one preheating the other and .the preheated burner having vaporizing means and air supply means including a fan motor, mechanism for starting and Stopping said preheated burner while maintaining said preheating burner and fan motor in operation, means for starting and stopping both of said burners, and means responsive only to the operation of said starting and stopping means for maintaining said ian motor in operation a suiiicient time after stopping of said burners to eliminate smoking of fuel in said vaporizing means.

' 13. In combination, aY pair of oil burners having oil supplies and one burner preheating the other and the latter having an air supply including a fan motor, valves controlling said oil supplies, a manually operable control member movable into position to start and stop both burners, ignition mechanism for said preheating burner including time delay control means controlled by operation of said member, mechanism likewise controlled by operation of said member for effecting automatic starting of said burners including means for opening the preheating burner valve upon operation of said ignition mechanism and having time delay con- -trol means for opening said preheated burner valve following a predetermined preheating operation, and means responsive to the burner temperature of said preheated burner for continuing the operation of said fan motor for a time interval after said control member has been moved into stopping position.

14. In combination, a. pair of oil burners having oil supplies and one burner preheating the other, electromagnetically operated valves controlling said oil supplies, ignition mechanism for the preheating burner, and electric control mechanism for said valves and electric ignition mechanism having a. manually operable switch, operating coils for said valves, means for energizing the coil of the preheating burner valve to open .the latter upon closure of said switch, electrically operated time delay switch means for cutting out said ignition mechanism, and electrically operated time delay switch means for subsequently energizing the coil of the preheated H burner valve to open the latter while maintaining the oil supply to said preheating burner.

15. In combination, a pair of oil burners having oil supplies and one burner preheating the other, electromagnetically operated valves controlling said oil supplies, ignition mechanism for the preheating burner, operating coils for said valves, a manually operable switch for energizing the coil of .the preheating burner valve to open the latter upon closure of said switch, and electrically operated time delay switch means including a heating coil and means actuated thereby to open the circuit ofY said ignition mechanism and a second heating coil and means actuated :thereby subsequently to close the circuit of the coil for the preheated burner valve after different time intervals while maintaining the oil supply to said preheating burner.

16. In combination, a pair of oil burners having oil supplies and one burner preheating the other, electromagnetically operated valves controlling said oil supplies, ignition mechanism for the preheating -bu-rner, and electric control mechanism for said valves and ignition mechanism having a manually operable switch, operating coils for said valves, means for energizing the coil of the preheating burner valve to open the latter upon closure of said switch, an electrical-r ly operated time delay switch including electric heating means adapted to cut out said ignition mechanism, and a second electrically operated time delay switch including electric heating means adapted to open the preheated burner valve, said time delay switches operating after different time Vintervals and having electromagnetically operated relays controlling ythe current flow l0 through said heating means while maintaining 'the oil supply to said preheating burner.

17. In combination, a pair of oil burners having oil supplies and one burner preheatlng the other, electromagnetically operated valves controlling said oil supplies, ignition mechanism for the preheating burner, electric control mechanism for said valves and ignition mechanism having a manually operable switch, operating coils for saidvalves, means for energizing the coil of the preheating burner valve to open the latter upon closure of said switch, an electrically operated time delay switch for cutting out said ignition mechanism, a second electrically operated time delay switch including electric heating means adapted to subsequently energize the coil to open the valve of the preheated burner, air supply-means for the preheated burner including a fan motor energized by said control mechanism upon closing the preheated burner valve, and temperature rponsive means in circuit with said fan motor and responsive to changes in tem- 15 perature of the preheated burner for maintainsaid manually operable switch. 

